Boeing has flagged a software glitch on the 737 MAX that can interrupt automated vertical navigation in a narrow missed-approach scenario, prompting the US Federal Aviation Administration to review the issue and consider immediate action if it finds a safety concern. The problem comes as Boeing pushes for certification of the 737 MAX 10 and continues work to bring the MAX 7 into service.
The issue arises when a crew performs a missed approach, then changes the pre-programmed flight path on a precision approach with autopilot engaged. In that sequence, the flight management computer can cause VNAV to drop out, leaving pilots with a less automated pitch-control mode. Boeing has told operators the problem is not an immediate safety risk and is working on a software update, while the FAA is convening a Corrective Action Review Board to assess the proposed fix.
The review adds pressure to Boeing’s narrowbody certification programme at a sensitive moment. Airlines including Southwest and United are pressing for deliveries that are not affected by the software version under scrutiny, and Boeing has already circulated guidance to operators while preparing an interim response for crews. The permanent fix had previously been planned for later in the decade, underlining the potential for the issue to affect both certification timing and delivery planning.